fix(dashboard): fold one-field doctor category into general tab

doctor.live_probe_timeout is the only schema-surfaced doctor.* field;
merge it into the general tab per the no-orphan-category invariant.

hermes_cli/web_server.py

@@ -1049,6 +1049,9 @@ _CATEGORY_MERGE: Dict[str, str] = {
     # `telemetry.shared_metrics.enabled` is the only schema-surfaced telemetry
     # field — fold it into security alongside the other privacy-posture toggles.
     "telemetry": "security",
+    # `doctor.live_probe_timeout` is the only schema-surfaced doctor field —
+    # fold it into general rather than spawning a one-field orphan category.
+    "doctor": "general",
 }
 
 # Display order for tabs — unlisted categories sort alphabetically after these.